多排桩非连续屏障对平面弹性波的隔离  

ISOLATION OF PLANE ELASTIC WAVES BY DISCONTINUOUS BARRIERS COMPOSED OF SEVERAL ROWS OF PILES

作　　者：徐平[1] 

机构地区：[1]郑州大学交通运输工程系,河南郑州450001

出　　处：《岩石力学与工程学报》2012年第A01期3159-3166,共8页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(51008286)

摘　　要：假定桩体的长度远大于直径,将多排弹性桩组成的非连续屏障对平面弹性波(P波和S波)的隔离简化成弹性波多重散射的二维平面问题,运用复变函数的保角映射方法和波场势函数展开法,根据桩体与周围土体介质完全联结(即应力和位移连续)的边界条件,得到散射和折射波场势函数展开式的待定复系数的理论解;通过分析位移比值(屏障后土体内某点由入射波和散射波产生的总位移与入射波单独产生的位移之比)的变化规律,对比单排、双排和3排桩屏障的隔离效果。研究结果表明:(1)当屏障的整体宽度和每排的桩数相同时,多排桩屏障对P波、SH波和SV波的隔离效果都随着桩排数的增多而提高;(2)当屏障整体宽度和桩总数相同时,紧密布置的单排桩对P波、SH波和SV波的隔离效果都比交错布置的双排桩更有效;(3)多排桩屏障对SH波和SV波的隔离效果比P波要好。The lengths of piles are considered as much larger than their diameters, so the isolation of incident plane elastic waves（P waves, and S waves） by discontinuous barriers composed of several rows of piles can be simplified as a two-dimensional plane problem. The conformal mapping method of complex functions and expansion method of wave field potential functions are adopted, the stresses and displacements at the boundaries between the piles and their adjacent soils are considered as continuous, and then the theoretical solutions about.the undetermined complex coefficients of scattering and infracting wave potential functions are obtained. By studying the normalized displacement amplitudes, which are the ratios of displacement amplitudes of soils behind the barriers caused by both the incident and scattering waves to those only by the incident waves, the isolation effects of the barriers composed of one, two and three rows of piles are compared, and the results reveal that： （1） When the barriers width and piles numbers of every row are the same, the isolation effect of P waves, SH waves and SV waves by the same barriers composed of several rows of piles all increase with the increasing rows number of piles. （2） When the barriers width and total piles number are the same, the isolation effect of P waves, SH waves and SV waves by one row of tight piles are better than that by two rows of staggered piles. （3） The isolation effects of SH waves and SV o waves are better than those of P waves by the same barriers composed of several rows of piles.

关 键 词：桩基础 多排弹性桩 非连续屏障 平面弹性波 隔离效果 隔振设计 

分 类 号：TU473[建筑科学—结构工程]